Method of making fabric reenforced rubber articles



May 16, 1933. I D. K. PQPE 1,909,892

METHOD 0F MAKING FABRIC REENFORCED RUBBER ARTICLES Filed April 29, 1931 2 Sheets-Sheet l INVENTOR Damas@- K. Paine 744m?, s. M

ATTORNEY May 16, 1933. D. K. POPE METHOD OF MAKING FABRIC REENFORCED RUBBER ARTICLES Filed April 29, 1931 2 Sheets-Shea#I 2 Pof BY s. 6 WML ATTORNEY lNvENToR Danigz K.

I' and configurations lmay I arecomposed of `aninteriorlayer of fabric- Patented May 16, 1933 DANIEL Kfrorn or ctavrzuaivinifoirx i s immer or Maxine reamearrivrorrceiijlmmrgnfnmm if i `rThis invention relates toI a method of.

making fabric reenforced' rubber articles andparticularly to a method `by which `integral one-piece articles` of various shapes' be formed ofrub-` ber covered fabric. p s I.

further vobject is to provide "a method of making articles of irregularcoutour which "and, an extrio'r lay(rv 0f rubber' "'Alfurther object is `to provideja method' of making articlesisuch` as above Areferred4 to in which a piece of frictiohed fabricis applied to a corerof curved or"irregular "contour in such ymanner as to lconformtot, the surface"A `of the core without wrinkling or`distortion, invvhic'h the fabric on the core is coated with raw rubber, and in which .the rubber article so formedis curedon the I A'furth'er object is to provide aiiuethod` in which vslits are formedin the fabric prior p to its application `to the core in Vsuch manner `that the fabric may be mad'eto `conform to*l the shape ofthe 'core' `and. providefa substantially continuous reenforcement for thev article formed on the core.'

A ,further object is t'o provide a method of i n making a one-piece fabric reenforced "rub-l 1 "'brfcover `for lthe `bod ysupporting springs n of motor vehicles which Ais Yadapted tov be Wrappedupori a ,spring on a vehicle and"4 A further object is vto provide a method",

`of making a one-piecefabric reenforced rubbern cover which is 'formed with bulges or pockets therein to accommodatethe projecting portions of 'a rebound clip on the spring,v the cover being formed to closely fit the 'springen oppositeusides of` the c-llip.

A 'further object is to 'provide a method .of y

forming a Cover adapted Eto 'be wrapped aboutand secured 'upon thefspring"l on a the 'cover is lto 'be applied,'the corey being. so

formed as to-accom'modatea width of fabricl l. greater than necessary to cover the. spring,v

lso thatIa-,cove'r is'formed which has flaps specification; inwhich; Fig. 1' is a perspective'k view showing al .vehicle by coatinga yfriction fabric Y.Wrapped 'upon Eau form' having a sha-pe i corresponding in `general to that dof `the spring t0 which*y spring.

adapted to :overlap along lthebottom "of thef j -the inventionmay be said tobomprisegthe" methodoas illustrated in 'the accompanying! drawings' hereinafter described, and particu# larly set forth in the appeudedc'laims', to,-

`skilled4 in the art to flwhi'chjv thel inventiozrf4 ap lertain's.'V

eference panying drawings forming `gether With such variations and' modifica-" tions thereof' as Will be apparent'ftofonef Shouldy be had "tohewcom a Pm of this core' upon* which a `spring cover fmayzb i. formed', the'core having apiece of friction'ed l fabric'applied thereto; n r

Fig. 2:15aSiae@1m/faimshowingl the over applled to a vehicle springl; w l

Fig: 3 is a plan view s owing a portion"A ofthe reenforcing fabric providedlwith' a" Zlg zag .slit in a portion thereof" whichen-Q 4gages a` projection on the core which en'- "u tion, these slits .in the'fabric enabling 'tbef ables the fabric tofc'onform to the projec-l :fabric to-be Wrapped Without `vvrinlclingr` over projections on the forming core; f

' iglic is a section taken'von the liueindia 0 1 4Fig; 5fis 'a section taken` on the line *.irldi-v` cated at 5 5 in 'Figl 2;

Fig.- 6 is a section takenon the line cated at 6 6 in Fig. 2;

Figzl? a section taken on the cated aty-' iny l Fig-. y l

indi- S a plan flew cffppamts" 'Whdi may be'mployed i in practicing the method l..

of the present invention invvhicha forluiugjg-s'; corey is` Wrapped'with frictionedV fabric,' the l" fabric covered 4core'dipped in liquid rubber UF ig. 9,is la side elevation cfa portie to apply a coating of .rubber .and .therubbe I" coated fabric cured Yon'the core i .I

n or for@ the apparatus kshowing dipping `tanks and"y curing ovens;

core ,With-the rubber .coated .fabric thereon,

the core being shownin the position in which Fig. 10 lis a perspective view A"is to be applied.

it is held during the 'dipping and curing operation used on motor vehicles to which is attached. a rebound clip 2 and an auxiliary clip 3 and to which is applied a fabric reenforced rubber cover 4 such as may be produced by the method of the present invention,"the

cover being provided withbulges or pockets.

5 and 6 to accommodate the projectingpor# tions of the clips 2 and .3 and having flaps 7 and 8 which overlap along the bottom of the; spring.` `The cover 4 has a snug fit throughout its length upon the spring except,` Where thespring clips are mounted and thegoverlapping flaps 7 and 8 may be se` `:cured together when the cover is appliedv to the spring by means of rubber cement.

' In making spring covers or other articles" by the method o f the present invention, each cover isv formed upon a core 9 which is pref- 'A'ferably composed of a material such as porcelain to which the rubber will not adhere,

when cured thereon and which has a fiat face 10 of la width corresponding to the `width of the top face ofthe spring toxwhich the cover -is'to be applied, and flat side faces lladjoining the -face 10 of gradually decreasingfwidth toward one end of the core and corresponding in size and shape to the -side faces' of the'spring to which the cover At the side thereof opposite the fiat face 10, the core 9 has opposite- 1y. inclined faces` 12 and 13 whichare dis'- posed at obtuse angles to the side faces 11 and which intersect at a centrally disposed longitudinally extending apex 14. The portions off the cover which fit upon the top and'sides of the spring 1 are lformed upon the faces 10 and 11 of the core and the uop'positely inclined faces 12` and 13 accom- 'modate fabric in excess of the width ofthe bottom of the spring to -form the overlapping flaps 7 and 8 of the cover.

In order to `form the bulges or pockets 5 and -with concave facesv18 merging into the flat/faces 11 of theI core.

'In forming the cover a trapezoidal piece rof fabric 19 of a size just sufiicientto wrap about and rcover the core with'the edgesof the fabric adjoining along the apex 14 is cut from a sheet of fabric which'has been' impregnated with' fraw rubber, the tacky sheet of impregnated fabric being known in lthe trade as frictioned'fabric. TA piece Of and 6 in the cover, the core 9 Iis provided.

frictioned fabric 19 when wrapped about the core 9 will firmly adhere to the core. The frictioned fabric 19 is provided with slits 20 which extend back and forth in zig zag fashion in the portions thereof which fit over the projections and 16 of the core, the slits extendingback and` forth yacross the fabric, providing interfitting y'tongues of fabric 21 which slide laterally with respect to each other as the portions of the fabric on opposite lsides of the slits are spread apart ,byv the projections of then'core, and

`forml openings 22 in the fabricso that the piece of., .fabric can.: be wrapped snugly around'the core without wrinkling. When the fabric is in place onthe core-.the slitted portions of thefabric extend overthe prol jections 15 and .16 thereof witlrvthe fabric., vtongues 21 extending. over the outer edges of the projections, so that they. will reene force the bulging portions of the cover.r

After the frictioned .fabric has beenap! pliedy to the core, a coating of rubber isf;

applied to the outersurface kofthe-fabric.;

by dipping the fabric coveredcore in `the raw.. rubber 1in liquid form, after which the rubber vis cured on the core. y w l f In 'order to support. the cores. during the dippingoperation, the cores 9 are provided l with hooks 23 by `meansof which they may be suspendedin horizontal position from carriers24 ,which travell on endless tracks 25'whlich, as shownin Fig.j 8 may have a portionthereof alongside a loading stationy 26, portions thereof over dipping tanks 27 and portions adjacent the tanks extending through `curing ovens 28, theendless track.y `25being provided .with dips 29 overeach.

of the tanks so that in thev travel ofzthe car- .105

riers ,along .the.- tracks, the Acores aref `im-lv mersed in the rubber Iin the tanks. vThe cores 9 are preferably suspended y from the carriers in a horizontal position with the proi jections 15 and 16 thereof on the under side, ,so that the yliojuidrubber deposited on thev fabric in the tank will flow downwardly over the projections 15 and 16 and complete-A vly fill the openings22 in the fabric. After A, .being dipped in al tank 27, the carriers with the cores thereon, pass through a ,curing oven 28, as many dipping tanksand curing ovens' being provided as may be necessary to apply a coating of rubber of the desired thickness on the fabric.` f

The rubber employed-may v,be a rubber. composition which is not deterioriated by oil or grease, such oil resisting compositions ,being well known in the art, or an ordinary rubbermav be "used: in which case the ex- .teriorrof the cover may be coated with an` oil resistant varnish which may be applied after Vthe nal curingoperation by dipping` i the rubber covered cores' in" a varnish `tanksuch asA the tank 30 shown fin Fig. 8;l y

vAfter the cores with the fabric thereon.v

11sl y have been dipped and cured, a fabric reenforced rubber tube is formed on the core, and, after the curing operation, this tube may be slit from end to end along the apex 14 of the core and stripped from the core.

It will be observed that the corners of the core are so disposed that they form bends in the spring cover which fits upon the corners of the vehicle spring, and by reason of the fact that the dimensions of the facss l0 and l1 of the core correspond exactly to the dimensions of the top and side faces of the spring the cover will fit snugly Without Wrinkling upon the spring, and the fiaps 7 and 8 Will lie fiat in overlapping relation against the bottom of the spring. If desired, one of the flaps may be rou hened While on the core, to enable the rub er cement to make a stronger union between the contiguous faces of the flaps.

It will be apparent that the present invention provides a very rapid and economical method of manufacturing spring covers and that the method produces spring covers which are attractive in appearance and which Will have a tight fit on the spring when applied thereto.

Furthermore, it is to be understood that the particular form of product shown and described, and the particular procedure set forth, are presented for purposes of explanation and illustration and that various moditications of said product and procedure can be made Without departing from my invention as defined in the appended claims.

What I claim is:

1. The herein described method of making fabric reenforced rubber spring covers which consists in Wrapping a piece of frictioned fabric, corresponding in size and shape to the cover to be produced, snugly upon a longitudinally tapering core of substantially polygonal cross section which has faces of substantially the size and form of the top and side faces ofthe spring, the remaining surface portions of the core being of greater area than the bottom face of the spring to accommodate an excess of fabric, coating the frictioned fabric on the core With raw rubber and curing the rubber on t the core to form a fabric reenforced rubber tube on thecore, and slitting the tube longitudinally along the side of the core on which the excess of fabric is placed to provide a cover adapted to be wrapped about a spring and having flaps adapted to overlap along the bottom of the spring.

2. The herein described method of maks ing fabric reenforced rubberspring covers which consists in cutting out a piece of frictioned fabric of the size and shape of the cover, cutting zig zag slits in the portions of the fabric in which bulges are to be formed, Wrapping the fabric snugly on a longitudinally tapering core of substantially polygonal cross section 'which has facesof subi stantiallyfthe sizeandformiof the topand side faces of the spring to which the eover! 'l iswtobe applied and Whiclfhas outwardly vprojecting portions engaged bythe slitted portions ofthe fabric, coatingthe fabric on f the corevvith raw rubberand curing the rub,4

tions of the lfabric in `-which` bulges arefgto.

be formed, wrapping thefabric snugly on a` longitudinally taperingy core ofv substantial` ly polygonal cross sectionvvvhich has faces of;r substantiallyvthe size .and form of thetop and side facesof `the spring' to Which' theL cover `isftov appliedi andY Which has outwardlyprojectingportions engaged vby the'V slitted portions ofthe fabric, the side of1 theV core oppositej thatv corresponding to Vthe1 top face ofi the spring having a surface area u greater than that of the bottom of the spring tol accommodate a greaterwidth of fabric, coating thefabric on thevcore with r-awrubf bery and curing the rubber to forma fabric reenforced tube on thecore, and slitting the tube fromend to end centrally. of; the side thereof having-the fexcess-width of fabric to,provide;'a coveryadapted', to be Wrapped. about 'a' spring and having flaps which overl; lap along thebottom ofthe spring.` j f e f4; The herein described method of malring fabric reenforced .rubber spring covers* which 'consistsin cutting out apiece of.fric. tioned fabric; of the size andH shapeof the' cover,cutting'zig zag slits in the portionsof.. thefabricin Whichbulges are to be formed,l which Iprovidefinterfitting tongueso'f fabric, wrappingrthe fabric snugly yupon a longi-L tudinallyigtapering core of substantially polygonalcrosssection which has faces of substantially` `the size and form. of thetop andv side faces of the spring and which has diagonally/,extending projections at-the corners Whichfhave concave faces merging into theifaces of thecorevvhich correspond to the top and side faces of the spring, said slitted portions of the fabric engaging said projections with the tongues interfitting over the tips of the projections, dipping the fabric covered core in a tank of raw rubber in liquid form and curing the rubber to form a fabric reenforced tube on the core, and slitting the tube from end to end to provide a cover adapted to be Wrapped about a spring.

5.. The herein described method'of mak- ITI,

ing fabric reenforcedrubber springooversi whichc'onsists incuttingout"aJ pieceofffrioL-l 1, v tioned fabric'of the sizeandshape-fof the:

cover, cutting zigzag slits -vinl ytheportions? of the fabric in which rbulges: aretowllnaI formed, vWhich..provide intertting tongues of y fabric, Wrappingthe fabric snugly' upon a longitudinally tapering ycore of fsubstanr? tially polygonal cross section which faces of substantiallythefsize and lfornrof the'ltop and side .facesof-lthe yspringend Which has diagonally extending 'projections` at the corners which have concave-faces merging into the` faces of the. core `which correspond to the top and side faces y-of the spring, said lslitted portionsof the fabrie' engaging said projections with thetongues interitting over .the tip of 2 the 'proj e'ctions,` supporting the fabric yWrapped core in La' substantially :horizontal position with' said projections on the undersidethereof,` dip# ping the core in liquid rubberwhilein said horizontal position so that=the rubber will flow over said' projecting-'tips and fill the openings in the fabric caused by-` the spread-'- ing of the slittedportions,curingftherrubbemand slitting the tubel ofA rubber on the core from end toA end tojprovide a spring cover-adapted' to' be `Wrapped upon a spring on avehicle.

6. The herein' described' method .of -making fabric reenforced spring -coversadapt ed to bcl Wrapped 'about a spring. on axyehicle fwith the edges thereof overlappingalongthe'bottom of the spring Whichlconsistsi-nf ,Wrapping a piecevof frictioned lfabricupon a 4iorigitudinally 'tapering core having Aone face-of a size and shapecorresponding tol the top faceof the spring to which the cover is to -be applied yand side faces correspond-- ing'in size and shape=to the sidesof the spring, the side vofsaid core4 opposite 'fthe first mentioned face having oppositely in'v clined surfaces disposed-at obtuse angles 1tothe side faces, coating the 'fabrieon the' core with rubber and curing the-rubber to form: aA

fabric reenforced tube onf'the corelandslit=l y tinglt-he tube along'the apex. of saidfoppov sitfely inclined'surfaces yt0 4provide -al cover. which fits `upon the top andside-f faces ofthe spring and Which has flaps adapted'to overlap alongthe bottom of thespring-.fv

In testimony `whereof Il -afiix my signature.

DANIEL KzPOPE; f 

